JPH04162234A - Recording method for magnetic field modulation - Google Patents

Abstract

PURPOSE:To eliminate occurrence of jitter or the like in reproduction by a method wherein data recorded on the opposite ends of a land part of a magnetooptical recording medium and on groove parts provided in the opposite ends of the land part are erased just after the data are recorded on the magnetooptical recording medium. CONSTITUTION:Beams 6 for erasing signals on the opposite ends of a track are provided behind a beam 5 for recording. Just after data are recorded on a magnetooptical recording medium, the data recorded on the opposite ends of a land part 1 of the magnetooptical recording medium and on groove parts 2 provided in the opposite ends of the land part 1 are always erased thereby and the same state as a background is attained. Even when there are leftovers behind erasure on the occasion of overwriting, accordingly, they can be erased immediately after the erasure. Thereby the part of the leftovers behind the erasure can be eliminated from the data after recording and occurrence of jitter in reproduction can be eliminated.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetic field modulation recording method for recording data on a magneto-optical recording medium, and in particular to a recording method that reduces erasures that occur when performing magnetic field modulation recording. It is related to.

[Conventional technology]

In magneto-optical recording for recording data on magneto-optical recording media, the magnetic field modulation recording method is being researched and developed as a powerful technology for overriding.

FIG. 4 is a diagram showing the configuration of an example of an apparatus for implementing a conventional magnetic field modulation recording method. In FIG. 4, 11 is a magneto-optical recording medium, 12 is an optical pickup that irradiates a light beam onto the magneto-optical recording medium 11, and 13 is a magneto-optical recording medium 11 that applies a recording intensity #A magnetic field according to data. magnetic head,
14 is a driver for driving the magnetic head 13;
15 is a spindle motor for rotating the magneto-optical recording medium 11;

In the apparatus shown in FIG. 4, data recording is performed by continuously emitting a light beam emitted from an optical pickup 12 with the power necessary for recording, and heating the location of the magneto-optical recording medium 11 to be recorded to a temperature above the Curie point. In this state, a modulated magnetic field for recording according to data is applied from the magnetic head 13 thereon.

The magnetic head 13 uses a floating head used in magnetic disk drives because it is necessary to modulate the coil at high speed to obtain a magnetic field of necessary strength and to position the magnetic head on the recording track at high speed. be done.

[Problem to be solved by the invention]

However, when data is recorded using the magnetic field modulation method described above, especially when overriding, the following problems occur as described in the IEICE Magnetic Recording Study Group Material MR89-54r Magneto-Optical Disk Magnetic Field Modulation Override. there were.

In other words, if an override is performed using a light beam with a lower power than the power used to initially record data, or the spot of the light beam becomes large, the land area where the data should be recorded and the land area are affected. When overriding by off-tracking to the group section of a track consisting of group sections provided at both ends, there is a big problem that part of the previous data remains and unerased data occurs, resulting in jitter. was there.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a recording method for magnetic field modulation that eliminates unerased data during override and eliminates jitter.

[Means to solve the problem]

The recording method for magnetic field modulation of the present invention is a magnetic field modulation recording method for recording data on a magneto-optical recording medium. The feature is that the data recorded in the provided group section is erased.

[Function] In the above configuration, an erasing beam for erasing signals at both ends of the track is provided after the recording beam, and immediately after data is recorded on the magneto-optical recording medium, the land portion of the magneto-optical recording medium is erased. Since the data recorded in the group parts provided at both ends of the land part and both ends of the land part are always erased to maintain the same state as the background, even if there is any unerased data left during overriding, it can be erased immediately afterward.

As a result, according to the recording method of the present invention, it is possible to eliminate unerased portions from data after recording, and it is possible to eliminate jitter during reproduction.

〔Example〕

FIG. 1 is a diagram showing the configuration of an example of the arrangement of light beams for carrying out the recording method of the present invention. In FIG. 1, ■ is a land portion on which data is to be recorded on the magneto-optical recording medium, and 2 is a group portion provided at both ends of the land portion 1 for positioning the beam on the land portion 1. 1 and group parts 2 at both ends thereof constitute a track 4.

Further, 5 is a recording and reproducing beam for applying the power necessary for recording during recording and reading data during reproducing, and 6 is a beam for recording and reproducing the recorded data near both ends of the land portion 1 and the land. an erasing beam for erasing data recorded in group part 2 that protrudes from part 1;
7 is a verification beam for verifying data recorded during recording.

The distance between the recording and reproducing beam 5 and the erasing beam 6 should be at least 50 to 10 mm, because if the distance is too close, the effect of the modulated magnetic field used for data recording will be exerted on the erasing beam 6.
It is necessary to separate the 0μ steel. Further, tracking during override recording by the recording/reproducing beam 5 can be performed by the rear erasing beam 6. Furthermore, the power of the recording/reproducing beam 5 and the erasing beam 6 needs to be greater than the power of the tiLW beam 7.

FIGS. 2 and 3 are diagrams for explaining an example of the recording method of the present invention, respectively. The example shown in FIG. 2 shows the operation when the recording/reproducing beam 5 is shifted toward the outer circumference of the magneto-optical recording medium.

In this case, the data to be recorded is recorded offset from the center of the land portion 1 in the outer circumferential direction, but the erasing beam 6 on the outer circumference side is applied to the end of the land portion l and the group portion 2 protruding from the land portion 1. Since the recorded data is erased, any unerased data can be removed.

Further, the example shown in FIG. 3 shows the operation when the recording ampholytic beam 5 is shifted toward the inner circumferential direction of the magneto-optical medium. In this case, data is recorded offset from the center of the land portion 1 toward the inner circumference, but as in the example shown in Fig. 2, unnecessary data portions are erased by the erasing beam 6 on the inner circumference side. This allows you to eliminate unerased areas.

In the above example, the data recorded during recording can be helified by the confirmation beam 7, and during signal reproduction, the erasure beam 6 and the confirmation beam 7 are turned off, and the recording/reproduction beam 5 is emitted with the reproduction power. This allows the data to be read.

The present invention is not limited only to the embodiments described above, and numerous modifications and changes are possible. For example, in the embodiment described above, ii! Erasing beam 6 before and after recognition beam 7
However, it is clear that the relative positional relationship between these beams is not limited to this.

〔Effect of the invention〕

As is clear from the detailed explanation above, according to the present invention, immediately after data is recorded on a magneto-optical recording medium, groups are formed at both ends of the land portion of the magneto-optical recording medium and at both ends of the land portion. Since the data recorded in the section is erased, even if there is any unerased data during override, it can be erased, and jitter etc. during playback can be eliminated.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of the configuration of the arrangement of light beams for carrying out the recording method of the present invention, FIGS. 2 and 3 are diagrams each for explaining an example of the recording method of the present invention, and FIG. 1 is a diagram showing the configuration of an example of an apparatus that implements a conventional recording method. ■...Land part 2...Group part 4...
Track 5... Beam for recording/reproduction 6... Beam for erasing 7... Beam for confirmation Figure 1 Figure 2

Claims (1)

[Claims] 1. In magnetic field modulation recording that records data on a magneto-optical recording medium, after data is recorded on the magneto-optical recording medium, data is recorded on both ends of the land portion of the magneto-optical recording medium and on the group portions provided at both ends of the land portion. A recording method for magnetic field modulation characterized by erasing data.